The acquisition of comprehensive datasets containing phenotypic, biological, psychological and social information is expensive and labor-intensive but is necessary for the investigation of aging and related disorders. The Brain and Ageing Research Program ('BARP', University of New South Wales, Australia) has committed substantial resources over the last decade to establish cohorts and collect rich multi-faceted longitudinal datasets on older individuals in Australia. The cohorts include community-dwelling non-demented individuals, twin pairs, centenarians/ near-centenarians and stroke survivors, and the data ranging from biochemical, genetic & medical imaging data through to detailed neuropsychological, behavioral and demographic information collected longitudinally over multiple waves. The current project proposes to re-format these extensive databases for release into the public domain so that the data can be shared openly and analyzed by researchers around the world. This will contribute to the international effort to investigate aging and age-related brain diseases. The BARP databases comprise 4 longitudinal cohort studies: 1. The Memory & Ageing Study (MAS): a study of 1000+ community-based non-demented individuals from the Eastern suburbs of Sydney (Australia) which began in 2005 and collects information from its participants on an annual basis, with detailed assessments every two years, including neuroimaging, genetics and proteomics. Its primary aim is to determine the risk and protective factors in relation to cognitive decline in aging and dementia (n = 1000+; 2000+ variables per assessment). 2. The Older Australian Twins Study (OATS): a study of 300+ Australian monozygotic and dizygotic twin pairs which began in 2007 and collects information on an annual basis. It aims to determine the relative impact of genetics vs. environmental factors in relation to both cognitive decline and healthy aging (n = 600; 2000+ variables per assessment). 3. The Sydney Centenarian Study (SCS): a study of individuals aged 95+ years of age which began in 2008 and collects information from its participants on a 6 monthly basis (max. 3 assessments). It aims to compare cognitive decline and healthy aging in relation to exceptional longevity, as well as investigating the so-called 'super healthy' human phenotype described by compression-of-morbidity theories (n = 250+; 1000+ variables per assessment). 4. The Sydney Stroke Study (SSS): a study of stroke patients and healthy controls assessed 3-6 months after the stroke then 1, 3 and 5 years later (n = 200 stroke; 100 controls; 1000+ variables per assessment). All 4 studies collected data on cognitive phenotypes (e.g. dementia/MCI+subtypes/healthy), neurocognitive assessment, psychosocial questionnaires, medical history + exam, medication use, neuroimaging, blood chemistry, proteomics and genetics/genomics (no proteomics or genetics for SSS). All studies collect data longitudinally and thus the BARP databases represent a truly rich and valuable potential data source for researchers worldwide. PUBLIC HEALTH RELEVANCE: The investigation of aging and age-related neuropsychiatric disorders is dependent upon the availability of well-characterized cohorts of aging individuals who have been assessed longitudinally. The Brain and Ageing Research Program at the University of New South Wales has established a number of longitudinal cohorts with extensive documentation. This proposal will see the public release of four longitudinal databases containing data (up to 2000+ variables per dataset) on over 2000 elderly individuals ranging from the healthy to those with dementia, and inclusive of four cohorts: community dwelling elderly (aged 70-90 years), elderly twins (aged >65 years), centenarians/ near-centenarians and stroke sufferers. The data include neuropsychiatric and medical assessments, neuroimaging, genetics and proteomics, and these cohorts will therefore provide a unique international resource for the investigation of ageing and associated disorders by researchers world-wide.